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A088979
a(n) = n! - ((n-1)!!)^2.
1
1, 2, 15, 56, 495, 2736, 29295, 215424, 2735775, 25171200, 370945575, 4103654400, 68916822975, 891494553600, 16813959537375, 249145395609600, 5214921734397375, 87125481883238400, 2004231846526284375, 37283094761472000000, 934957186489800849375
OFFSET
2,2
FORMULA
E.g.f.: 1/(1 - x) - (1 + arcsin(x))/sqrt(1 - x^2). - Benedict W. J. Irwin, Oct 14 2016
MATHEMATICA
Table[CoefficientList[Series[1/(1-x)-(1+ArcSin[x])/Sqrt[1-x^2], {x, 0, 20}], x][[n]](n-1)!, {n, 3, 20}] (* Benedict W. J. Irwin, Oct 14 2016 *)
CROSSREFS
Cf. A006882.
Bisection gives A151816.
Sequence in context: A142861 A305673 A268761 * A265909 A034571 A295828
KEYWORD
nonn
AUTHOR
Vladeta Jovovic, Oct 31 2003
EXTENSIONS
More terms from Ray Chandler, Nov 06 2003
STATUS
approved